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I:\CIRC\MSC\01\MSC.1-Circ.1598.docx E 4 ALBERT EMBANKMENT LONDON SE1 7SR Telephone: +44 (0)20 7735 7611 Fax: +44 (0)20 7587 3210 MSC.1/Circ.1598 24 January 2019 GUIDELINES ON FATIGUE 1 The Maritime Safety Committee, at its seventy-first session (19 to 28 May 1999), considered the issue of human fatigue and agreed to develop practical guidance to provide appropriate information on fatigue to all parties concerned. 2 Consequently, at its seventy-fourth session (30 May to 8 June 2001), the Committee approved MSC/Circ.1014 on Guidance on fatigue mitigation and management. 3 The Committee, at its ninety-fourth session (17 to 21 November 2014), agreed to undertake a revision of the Guidance on fatigue mitigation and management and instructed the Sub-Committee on Human Element, Training and Watchkeeping (HTW) to conduct the review. 4 Accordingly, the Committee, at its 100th session (3 to 7 December 2018), approved the annexed Guidelines on fatigue, finalized by the HTW Sub-Committee, at its fifth session (16 to 20 July 2018). 5 Member States are invited to: .1 bring the Guidelines to the attention of their maritime Administrations and all stakeholders, including seafarers, companies, naval architects/ship designers and training providers; .2 use the Guidelines as a basis for disseminating information on fatigue (for example by means of pamphlets, video training modules, seminars and workshops); and .3 take the Guidelines into consideration when determining minimum safe manning. 6 Companies are strongly urged to take the issue of fatigue into account when developing, implementing and improving safety management systems under the ISM Code. 7 This circular supersedes MSC.1/Circ.1014 on Guidance on fatigue mitigation and management, approved on 12 June 2001. ***
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  • I:\CIRC\MSC\01\MSC.1-Circ.1598.docx

    E

    4 ALBERT EMBANKMENT

    LONDON SE1 7SR Telephone: +44 (0)20 7735 7611 Fax: +44 (0)20 7587 3210

    MSC.1/Circ.1598 24 January 2019

    GUIDELINES ON FATIGUE

    1 The Maritime Safety Committee, at its seventy-first session (19 to 28 May 1999), considered the issue of human fatigue and agreed to develop practical guidance to provide appropriate information on fatigue to all parties concerned. 2 Consequently, at its seventy-fourth session (30 May to 8 June 2001), the Committee approved MSC/Circ.1014 on Guidance on fatigue mitigation and management. 3 The Committee, at its ninety-fourth session (17 to 21 November 2014), agreed to undertake a revision of the Guidance on fatigue mitigation and management and instructed the Sub-Committee on Human Element, Training and Watchkeeping (HTW) to conduct the review. 4 Accordingly, the Committee, at its 100th session (3 to 7 December 2018), approved the annexed Guidelines on fatigue, finalized by the HTW Sub-Committee, at its fifth session (16 to 20 July 2018). 5 Member States are invited to:

    .1 bring the Guidelines to the attention of their maritime Administrations and all stakeholders, including seafarers, companies, naval architects/ship designers and training providers;

    .2 use the Guidelines as a basis for disseminating information on fatigue (for

    example by means of pamphlets, video training modules, seminars and workshops); and

    .3 take the Guidelines into consideration when determining minimum safe

    manning.

    6 Companies are strongly urged to take the issue of fatigue into account when developing, implementing and improving safety management systems under the ISM Code. 7 This circular supersedes MSC.1/Circ.1014 on Guidance on fatigue mitigation and management, approved on 12 June 2001.

    * * *

  • MSC.1/Circ1598 Annex, page 1

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    ANNEX

    GUIDELINES ON FATIGUE

    INTRODUCTION

    1 For the purpose of the Guidelines, the following definition for fatigue is used:

    "A state of physical and/or mental impairment resulting from factors such as inadequate sleep, extended wakefulness, work/rest requirements out of sync with circadian rhythms and physical, mental or emotional exertion that can impair alertness and the ability to safely operate a ship or perform safety-related duties."

    2 Fatigue is a hazard because it may affect a seafarer's ability to do their job effectively and safely. Importantly, fatigue affects everyone regardless of skill, knowledge and training. The effects of fatigue can be particularly dangerous in the transportation sector, including the shipping industry. All stakeholders should be alert to the factors which may contribute to fatigue, and make efforts to mitigate and manage the risks posed by fatigue. 3 Effectively dealing with fatigue in the maritime environment requires a comprehensive and holistic approach that recognizes ship design, and the roles and responsibilities of all stakeholders in the mitigation and management of fatigue. An effective fatigue management strategy begins with determining operational workload requirements and matching onboard manning levels and onshore support resources, combined with efficient management of workload and hours of work and rest on board the ship. There is no one-system approach to addressing fatigue, but there are certain principles that should be addressed in order to gain the knowledge and the understanding to manage this human element issue. Objective 4 The Organization has developed these Guidelines to assist all stakeholders in better understanding their roles and responsibilities in mitigating and managing the risk of fatigue. 5 The Guidelines provide information on the causes and consequences of fatigue, and the risks it poses to the safety and health of seafarers, operational safety, security and protection of the marine environment. It has been prepared to assist all stakeholders in contributing to the mitigation and management of fatigue. Organization 6 The Guidelines are composed of modules each devoted to an interested party. The modules are as follows:

    .1 Module 1 Fatigue

    .2 Module 2 Fatigue and the company

    .3 Module 3 Fatigue and the seafarer

    .4 Module 4 Fatigue, awareness and training

    .5 Module 5 Fatigue and ship design

    .6 Module 6 Fatigue, the Administration and port State Authorities

    .7 Appendix 1 Examples of sleep and fatigue monitoring tools

    .8 Appendix 2 Example of a fatigue event report information

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    How to use these modules 7 The modules are all interrelated; it is recommended that all parties become familiar with module 1, which contains general information on fatigue. It may be beneficial if the reader (interested party) becomes familiar with modules other than the immediately applicable one. 8 These guidelines should be taken into consideration when:

    .1 developing, implementing and maintaining safety management systems under the ISM Code;

    .2 promoting fatigue mitigation and management; .3 promoting awareness of the causes and consequences of fatigue and

    developing and delivering training programmes and courses; .4 conducting casualty or accident/incident investigations; and .5 preparing applications for minimum safe manning documents or when

    determining minimum safe manning levels for ships. Future work 9 These Guidelines are a living document; they should be updated periodically as research reveals new information and new methods are uncovered to deal with the issue of fatigue.

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    MODULE 1

    FATIGUE Introduction 1 Fatigue is a hazard that affects safety, health and well-being. It presents a considerable risk to safety of life, property, health, security and protection of the marine environment. 2 This module provides a general overview of fatigue and its causes and consequences. This knowledge is important for developing strategies to reduce the risk of fatigue and related incidents. 3 It is recommended that all parties become familiar with module 1 prior to using modules 2 to 6. Fatigue and life on a ship 4 There is a common misconception that fatigue "comes with the job"; while not particular to the maritime industry, it is certainly pervasive within it. Fatigue is a hazard and needs to be addressed. 5 Fatigue is a problem for all 24-hour-a-day transportation modes and industries, including the maritime industry. However, operational aspects associated with the maritime industry are also more complex than those associated with other industries. For example, variety of ship-types, the pattern and length of sea passage, the number of port visits and port rotations, and the length of time a ship remains in port, all present unique combinations of potential causes of fatigue. 6 The demanding nature of shipping means that:

    .1 seafarers may be required to work long and irregular hours; .2 seafarers may spend an extended period of time working and living away

    from home, on a ship that is subject to unpredictable environmental factors (i.e. changing weather conditions);

    .3 the ship is both a seafarer's workplace and their home while on board; and .4 while serving on board the vessel, there may not be a clear separation

    between work and recreation, which can influence their mental and emotional well-being.

    7 Technology is sometimes seen as a way to improve the efficiency of work systems. However, technology changes the nature of work and alters workload, therefore it is important to evaluate the impact of technological changes on crew workload and consequently fatigue.

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    Causes of fatigue 8 Fatigue is caused by a range of factors, but is primarily caused by:

    .1 lack of sleep, i.e. inadequate restorative sleep; .2 poor quality of sleep and rest; .3 work/sleep at inappropriate times of the body clock (circadian rhythm); .4 staying awake for long periods; .5 stress; and .6 excessive workload (prolonged mental and/or physical exertion).

    9 There are many ways to categorize the causes of fatigue. To ensure thoroughness and to provide good coverage of most causes, they have been categorized into five general factors:

    .1 seafarer-specific factors;

    .2 management factors (ashore and aboard ship);

    .3 ship-specific factors;

    .4 environmental factors; and .5 operational factors.

    Seafarer-specific factors 10 The seafarer-specific factors are related to lifestyle behaviour, personal habits and individual attributes. Fatigue varies from one person to another and its effects are often dependent on the particular activity being performed. 11 The seafarer-specific factors include the following:

    .1 sleep and rest:

    .1 quantity, quality and continuity of sleep;

    .2 sleep disorders/disturbances; and .3 recovery rest/breaks;

    .2 body clock/Circadian rhythms; .3 psychological and emotional factors:

    .1 fear;

    .2 monotony and boredom; and

    .3 loneliness;

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    .4 health and well-being:

    .1 diet/nutrition/hydration; .2 exercise and fitness; and .3 illness and onset of illness;

    .5 stress:

    .1 skill, knowledge and training as it relates to the job; .2 personal issues of concern in personal life; and .3 interpersonal relationships at work or at home;

    .6 medication and substance use:

    .1 alcohol; .2 drugs (prescription and non-prescription); .3 supplements; and .4 caffeine and other stimulants;

    .7 age; .8 shift work and work schedules; .9 workload (mental/physical); and .10 jet lag.

    Management factors (ashore and aboard ship) 12 Management factors relate to how ships are managed and operated. These factors can potentially cause stress and an increased workload, ultimately resulting in fatigue. These factors include:

    .1 Organizational factors:

    .1 manning policies, levels, and retention; .2 role of riders and shore personnel; .3 administrative work/reporting/inspection requirements; .4 economics; .5 duty schedule-shift, overtime, breaks; .6 company procedures, culture and management style;

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    .7 shore-based support; .8 rules and regulations; .9 other resources; .10 maintenance and repair of the ship; and .11 drill schedules and training of crew;

    .2 Voyage and scheduling factors:

    .1 frequency and duration of port calls; .2 time between ports; .3 routeing; .4 weather and sea condition on route; .5 traffic density on route; .6 nature of duties/workload while in port and at sea; and .7 availability of shore leave.

    13 Module 2 provides recommended strategies for identifying, mitigating and controlling fatigue risks due to management factors. Ship-specific factors 14 These factors include some ship features that can affect and contribute to fatigue. Some ship design features affect workload (i.e. automation, equipment design and reliability), some affect the crew's ability to sleep, and others affect the level of physical stress on the crew (i.e. noise, vibration, accommodation spaces, etc.). The following list details some influential ship-specific factors:

    .1 ship design;

    .2 level and complexity of automation;

    .3 level of redundancy;

    .4 equipment design and reliability;

    .5 inspection and maintenance;

    .6 condition of the ship;

    .7 physical comfort in work spaces;

    .8 location of quarters;

    .9 ship motion; and .10 physical comfort of accommodation spaces.

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    15 Module 5 provides recommended strategies for identifying, mitigating and controlling fatigue risks due to ship-specific factors. Environmental factors 16 Environmental factors within areas in which seafarers live and work (both inside and outside the ship) may contribute to the onset of fatigue, and impact both sleep quantity and quality. Environmental factors to consider include noise and vibration, light, ship motion, temperature and humidity, and ventilation/air exchange. Long-term exposure to some of the following may impact a person's health:

    .1 Noise: (such as main engines, switchboards, TV and conversations) affects the ability to fall asleep, causing sleep loss, or it can alter one's sleep stage or depth of sleep.

    .2 Vibration: may affect sleep and fatigue. For example, alterations in vibration

    pattern may keep people awake, keep them from advancing into deeper sleep, or wake them up.

    .3 Light: (such as colour, intensity and exposure timing) is a complicated

    environmental factor. In addition, the use of electronic displays that emit blue light (such as computer screens, flat-screen televisions and smartphones) can also influence the body clock and can delay the onset of sleep, especially when used prior to bedtime.

    .4 Ship motion: depending on the weather and sea conditions, ship motion

    may interfere with sleep, cause motion-induced fatigue (fatigue caused by the extra energy expended to maintain balance while moving, especially during harsh sea conditions) and seasickness.

    .5 Temperature and humidity: all excessively hot and cold conditions will

    make an individual feel less alert and generally more fatigued. It is important that the shipboard temperature and humidity is controllable as this affects sleep and alertness. For example, the body sleeps best when the environment temperature is between 18ºC and 24ºC.

    .6 Ventilation/air exchange: in addition to controlling temperature and

    humidity, air quality (e.g. noxious odours or stale air) and design/placement of the ventilation system may interfere with sleep.

    Operational factors 17 While seafarers, companies, Administrations and port State authorities are the primary actors, many other stakeholders may also have an impact on shipboard operations and workload. Aspects to consider include inspections, surveys, audits, visits, reporting, security measures and any other additional tasks to be performed on board. Therefore, other stakeholders should contribute to the mitigation of fatigue by considering the impacts of their actions on shipboard operations. 18 Opportunities to mitigate the effects of these factors vary and will be discussed further in subsequent modules.

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    Important basic concepts in understanding fatigue 19 This section highlights some of the important concepts that provide an overall understanding about fatigue. The most significant aspects of fatigue are:

    .1 sleep; .2 body clock and the circadian rhythm; .3 time awake; .4 jet lag; .5 workload; .6 stress; .7 health; and .8 individual differences.

    Sleep 20 Not all sleep has the same quality or provides the same recuperative benefits. In order to satisfy the needs of the human body, sleep must have three characteristics to be most effective:

    .1 Quantity: it is generally recommended that a person obtain, on average, seven to eight hours of good quality sleep per 24-hour period. To perform adequately and effectively, a person needs the amount of sleep that produces the feeling of being refreshed and alert. Alertness and performance are directly related to sleep. Insufficient sleep will impair alertness. Only sleep can maintain or restore performance levels.

    .2 Quality: sleep is a highly organized sequence of events that follows a regular

    pattern of cycles between light and deep sleep. People need deep sleep. Deep sleep is a very restorative phase of sleep.

    .3 Continuity: sleep quality is dependent upon unbroken cycles of sleep,

    meaning sleep needs to be uninterrupted in order to retain its restorative value. Six 1-hour naps do not have the same benefit as one 6-hour period of sleep. The more fragmented the sleep cycle, the less restorative sleep becomes. This results in continued feelings of tiredness and often impacts performance and decision-making. If the time of sleep is out of synchronization with a person's body clock, it is difficult to sleep properly. It should be noted that the proportion of time spent in deep sleep decreases as we get older. Sleep also becomes more fragmented as we get older.

    21 Many factors contribute to sleep disruption and poor sleep quality; some are within our control while others are not:

    .1 environmental factors; .2 food;

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    .3 medication and substance use; .4 psychological factors; .5 sleep disorders; and .6 operational factors.

    22 Sleep debt is "insufficient accumulated sleep over multiple consecutive 24-hour periods". For example, if an individual needs eight hours of sleep per 24-hour period and only obtains six hours, they have accumulated a sleep debt. Sleep debt will affect an individual's level of alertness and performance. Long-term sleep debt may also lead to health problems. Over time, sleep-deprived individuals may become less aware of just how fatigued they are and become unable to judge their own level of performance. 23 When someone is woken up suddenly, the brain can have difficulty transitioning out of deep sleep. This is known as sleep inertia. Sleep inertia causes feelings of grogginess and disorientation, with impaired short-term memory and decision-making, and can last longer than 30 minutes. Sleep inertia can also occur following lighter sleep, but it tends to be longer and more disorienting when someone is woken abruptly out of deeper sleep. Body clock and the circadian rhythm 24 The time of day in which work takes place is a key risk factor in determining fatigue. This is because, independent of prior sleep and wakefulness, humans are biologically programmed to be active during the day and to sleep at night. 25 Each individual has a body clock, and this clock regulates the body's circadian rhythm. Our bodies move through various physical processes and states within a 24-hour period, such as sleeping/waking, and cyclical changes in body temperature, hormone levels, sensitivity to drugs, etc. This cycle represents the circadian rhythm. The body clock is synchronized to the traditional pattern of daytime wakefulness and night-time sleep. 26 The body clock makes a person sleepy or alert on a regular schedule whether they are working or not. In normal conditions, the sleep/wake cycle follows a 24-hour rhythm; however, the cycle is not the same for everyone. 27 Independent of other factors, fatigue is most likely, and when present, most severe, in the early hours of the morning, coinciding with the strongest drive for sleep. This period typically occurs between the hours of 3 and 5 a.m. and is commonly referred to as the window of circadian low (WOCL). 28 In general, seafarers working through the night may be at a higher risk of fatigue and have to make additional effort to maintain alertness and performance. This is supported by maritime studies and investigations in which fatigue was found to be a contributing cause in incidents that mainly occurred between midnight and 6 a.m. This indicates that from a maritime perspective high risk times may fall between these hours. 29 Apart from the WOCL, another distinct dip occurs between 3 and 5 p.m. (best known as the post-lunch dip).

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    30 The states of sleep/wakefulness and circadian rhythms interact in several ways:

    .1 The two can work against each other and thereby weaken or negate each other's effect. For example, a well-rested person is still affected by a circadian low point; conversely, a person who is sleep-deprived may feel a momentary increase in alertness due to a peak in circadian rhythm.

    .2 The two can also work in the same direction, thereby intensifying the effect

    they each have on a person's level of alertness. For example, when someone is sleep-deprived, a circadian low point will further exacerbate the feeling of sleepiness.

    31 For many seafarers, working patterns conflict with their body clock. Irregular schedules caused by shifting rotations, crossing time zones, etc. cause the circadian rhythms to be out of synchronization. As circadian adjustment to a particular pattern of work and rest is a relatively slow process (only adjust by an hour or two each day), constant changes impair sleep. Work that requires seafarers to be awake and working at night or early morning or to work for extended periods can cause disruptions to the body clock resulting in increased fatigue. 32 Even though the body clock can be reset over time, such as when changing times zones for an extended period, research shows that it cannot be permanently adjusted to a reversed cycle of work and sleep. Because the body clock may not adapt fully to altered sleep/wake patterns:

    .1 seafarers who work through the night can be expected to be sleepy and have to make additional effort to maintain alertness and performance; and

    .2 some seafarers may be fatigued at the start of their work period, as they

    adapt to their sleep routine. Time awake 33 How long an individual is awake affects sleepiness and consequently fatigue levels. The longer an individual has been awake, the poorer their performance. In general, the longer a seafarer remains awake, the stronger the drive for sleep, and the higher the levels of fatigue. During the first hours awake, the urge to sleep may go unnoticed, but as the amount of continuous wakefulness approaches 16 hours, awareness of the pressure to sleep is highly likely. This occurs sooner if the seafarer is already suffering from sleep debt. 34 Alertness and performance levels begin to decrease after a number of hours awake, with long duty periods associated with higher levels of fatigue than shorter duty periods due to extended wakefulness and demands on attention. In addition, the longer an individual has continuously been on a task without a break, the more likely they will be fatigued. Accident rates rise exponentially after 12 hours of consecutive work, particularly when working at night. 35 Long work hours are associated with poor performance, higher injury rates, and poorer safety and/or health outcomes (both mental and physical). Another important aspect to consider are work commutes. Many seafarers may be required to travel or drive long distances to the ship and then have to work.

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    Jet lag

    36 Jet lag occurs following long flights through several time zones. Seafarers crossing time zones to join their ship are exposed to a sudden change in the day/night cycle causing circadian disruption. It is a condition that causes fatigue in addition to sleep deprivation and irritability. The body clock will eventually adapt to a new time zone; however, depending on the new schedule, it takes several days to adjust. During the period of adaptation to the new time zone, common symptoms include wanting to eat and sleep at times that are out of step with the local routine, problems with digestion, degraded performance on mental and physical tasks, and mood changes. It is easier to adjust while crossing from east to west than from west to east.

    Workload 37 Workload refers to the type and intensity of tasks performed. Fatigue can occur when workload is either very high or very low. High and low workload may be present in a shipboard work environment, and are likely to induce fatigue. Fatigue resulting from workload becomes an increasing concern when combined with long periods of wakefulness and long duty hours.

    .1 High workload: both high physical workload and high mental workload (such

    as tasks with excessive demands on attention) may lead to fatigue. Examples of high workload routinely experienced on board ships include, but are not limited to, navigating in congested and dangerous waters; frequent port calls; navigating in conditions of poor visibility and/or bad weather; entering and exiting a port/harbour; having to complete multiple tasks; and tank cleaning and cargo operations.

    .2 Low workload: monotonous tasks, such as monitoring (of engine-room

    displays for example) can result in loss of interest and boredom, which also increases the effects of fatigue. This can be a particular problem when conducting bridge or engine monitoring and vigilance tasks across long periods of time. This can be readily seen when a person is required to maintain a period of concentrated and sustained attention, especially during the night (night duty, for example). People are generally not good at long duration vigilance tasks. Performance and alertness is further impacted if vigilance and monitoring tasks need to be carried out during the night-time hours, specifically between midnight and 5 a.m.

    Stress 38 Stress occurs when a person is confronted with an environment or situation that poses a threat or demand, and the individual becomes aware of his or her inability to cope or difficulty in coping with the environment (a feeling of being overwhelmed). This can result in reduced work performance and health problems. Stress is influenced by many characteristics of the work environment or issues with or changes to personal, family, or home environment. Stress can be caused by a number of factors, including:

    .1 environmental factors (e.g. constant or irregular noise, vibration, temperatures, weather, ice conditions);

    .2 personal circumstances (e.g. family problems, home sickness, isolation); .3 inadequate restorative sleep; .4 broken or interrupted sleep or rest periods;

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    .5 excessive working hours; .6 intense mental and/or physical workload; and .7 onboard interpersonal relationships.

    39 These stressors, and others, can impact the extent to which a seafarer is able to acquire sufficient sleep and consequently lead to fatigue. For example, family aspects that require attention but are beyond the seafarer's control may lead to short sleep duration and extended wakefulness. Seafarers may be away from home for extended periods of time. Loneliness, isolation, family conflict and concern about family members may provide enough stress to be considered risk factors. Health 40 Healthy lifestyle choices such as good physical fitness and a healthy diet have been reported to reduce fatigue and improve alertness and performance. Conversely, unhealthy lifestyle choices can negatively impact sleep and therefore contribute to fatigue.

    .1 Nutrition: a poor diet that does not include fresh fruit and vegetables can contribute to fatigue by adversely affecting a seafarer's health. In addition, irregular meal times can adversely affect digestion, which also follows the circadian rhythm. Digestion is programmed to be most efficient during the day and much less so at night. Food eaten at night is digested at a slower rate. This can often lead to feeling bloated or constipated and can cause heartburn and indigestion. Gastrointestinal upsets are very common in people who eat outside of traditional meal times. These upsets can be made worse by drinking tea, coffee or alcohol. Additionally, when lying down right after eating a large meal, acid reflux may occur. Night workers are 5 times more likely to get peptic ulcers than day workers.

    .2 Hydration: dehydration is also a factor that contributes to fatigue. When the

    body is low on water, it tries to conserve what it has left. It does this by reducing activity and making the body relax and slow down. When relaxed, people have a higher chance of falling asleep. Being dehydrated can also make people feel light-headed and cause headaches. In addition to maintaining cognitive function and alertness, drinking adequate water helps keep the digestive and circulatory systems operating properly. Water brings healthy nutrients to cells and carries away toxins.

    .3 Exercise and fitness: poor physical fitness adversely affects overall health

    and causes people to tire easily. Exercise speeds up metabolism and increases blood flow, which helps to keep a person awake. Exercise also helps the body cope with stress and can help individuals suffering from depression, a condition that can be characterized by fatigue. Physical exercise can also help reduce a person's susceptibility to certain diseases and infections. The inability to exercise is considered a risk factor because it is a circumstance that takes away a crew member's ability to increase physical fitness, enhance sleep, think clearly and manage stress.

    .4 Caffeine and other stimulants: caffeine can be found in beverages such as

    coffee, tea and some soft drinks. Caffeine can improve alertness and concentration in moderate doses, but it is not a substitute for adequate sleep and rest. Too much caffeine can have harmful effects such as increased

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    heart rate and blood pressure, and can cause fatigue in some people. It takes caffeine about 15 to 30 minutes to enter the body's system, and its physiological effects peak about an hour after the drug reaches the bloodstream. The effects of caffeine can vary highly from individual to individual and depend on physical condition, age, level of sleep debt, frequency of use and time of day. Generally, caffeine levels drop by half every five or six hours. Its effects can last long after consumption and may interfere with needed sleep. Caffeine shortens total sleep time by preventing sleep. Caffeine consumption can also cause dehydration.

    .5 Alcohol: although alcohol is a central nervous system depressant, it can

    impair the quality of sleep. Alcohol can lead to increased sleepiness and reduced alertness, even after the alcohol is no longer detectable. There are also serious health consequences related to the long-term abuse of alcohol. Many shipping companies have "zero alcohol tolerance."

    .6 Nicotine: nicotine is highly addictive and the dangers to health are well

    documented. Nicotine users generally have more disturbed sleep, typically taking longer to fall asleep and experiencing more wake time during a sleep period.

    .7 Drugs: it is important for seafarers to be aware of how drugs and

    supplements may affect their health and their sleep-wake cycles. Drug effects vary not only from person to person, they can also vary for the same person depending on time of day, mood, tiredness and the amount of food eaten. In addition, there are other drugs prescribed for specific ailments that can have sedating side effects. Some prescription drugs can affect people's ability to operate machinery (induce sleepiness). They may also interact with existing fatigue levels and other drugs (including alcohol) and supplements, further affecting performance. Some over-the-counter drugs used for pain relief or colds and flu may increase drowsiness and fatigue-related symptoms.

    .8 Supplements: there are now a number of nutritional supplements, natural

    products and energy drinks that are available on the market that directly influence sleep/wake states. Just because they are sold over the counter does not mean they are safe or appropriate for everyone. These products may interact with prescription or over-the-counter drugs to further affect performance. Individuals should proactively seek advice and guidance from their healthcare providers before using these products to learn about their appropriate use.

    .9 Sleep disorders: other health-related aspects are the wide variety of sleep

    disorders, which are known to disrupt the quality of sleep and make restorative sleep impossible, even when individuals spend enough time trying to sleep. The most common sleep disorders are obstructive sleep apnoea, insomnia, restless legs syndrome, shift work sleep disorder and narcolepsy. Undiagnosed or untreated sleep disorders can cause sleepiness problems. Sleep disorders pose a particular risk for seafarers, especially as maritime operations already expose seafarers to restricted sleep. Large numbers of individuals suffering from sleep disorders are unaware of and have not been diagnosed or treated for their disorder.

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    .1 Obstructive sleep apnoea (OSA) results in breathing being interrupted during sleep. Repetitive episodes of non-effective breathing, very shallow breaths or inadequate breaths lead to frequent partial arousals from sleep, resulting in ineffective sleep and sleep debt. OSA is a potentially serious sleep disorder resulting in excessive daytime sleepiness and can lead to cardiovascular problems. Sleep apnoea, which may be indicated by loud snoring with pauses of silence, often goes undiagnosed and untreated and has been known to be a contributing factor to incidents in all modes of transportation. Some risk factors include excessive weight, high body mass index (BMI), high blood pressure, smoking and diabetes.

    .2 Insomnia is the most prevalent sleep disorder and is characterized

    by an inability to fall asleep and/or by waking up during the night and having difficulty going back to sleep. Long-term insomnia is more common in women than men and tends to increase with age. Short-term insomnia may be caused by emotional or physical discomfort, stress, environmental noise, extreme temperatures or jet lag, or may be the side effect of medication. Secondary insomnia may result from a combination of physical or mental disorders, undiagnosed or uncontrolled sleep disorders and effects of prescription or non-prescription medications.

    .3 Restless legs syndrome (RLS) is a movement disorder that is often

    associated with a sleep complaint. People with RLS have unpleasant leg sensations and an almost irresistible urge to move their legs. Symptoms are worse during inactivity and often interfere with sleep. Sitting still for long periods becomes difficult; symptoms are usually worse in the evening and night and less severe in the morning.

    .4 Shift work sleep disorder is characterized by insomnia and

    excessive sleepiness affecting people whose work hours overlap with the typical sleep period. There are numerous shift work schedules (permanent, intermittent or rotating); consequently, the manifestations of this disorder are quite variable. Those with shift work disorder complain more of mood problems such as impatience and depression, as well as more self-reported health complaints such as ulcers and substance use.

    .5 Narcolepsy is a chronic sleep disorder that usually becomes evident

    during adolescence or young adulthood. The main characteristic of narcolepsy is excessive and overwhelming daytime sleepiness (even after adequate night-time sleep). A person with narcolepsy is likely to become drowsy or to fall asleep at inappropriate times and places, and in extreme cases during periods of activity. Daytime sleep attacks may occur without warning and may be irresistible. In addition, night-time sleep may also be fragmented.

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    Individual differences 41 Individuals respond to fatigue differently and may become fatigued at different times, and to different degrees of severity, under the same circumstances. There are also individual characteristics related to circadian rhythms. People can be characterized as morning or evening types depending on the period of the day when they perform at their best. Effects of fatigue 42 When a person is affected by fatigue, performance on the job can be significantly impaired. Impairment will occur in every aspect of human performance (physically, emotionally, and mentally) such as in decision-making, response time, judgement, hand-eye coordination and countless other skills. When impairment due to fatigue, such as impaired memory or poor communication, coincides with other risks in the environment, incidents can result. This is evidenced in a number of maritime casualties in which fatigue was a contributory factor. Maritime studies have also confirmed the association between fatigue and poor performance. 43 People are poor judges of their own level of fatigue, performance and decision-making. The following is a sample of fatigue's known effect on performance:

    .1 Fatigued individuals become more susceptible to errors of attention and memory (for example, it is not uncommon for fatigued individuals to omit steps in a sequence).

    .2 Fatigued individuals will often select strategies that have a high degree of

    risk on the basis that they require less effort to execute.

    .3 Fatigue can negatively affect an individual's ability to identify and respond to stimuli.

    .4 Fatigue can also negatively affect problem-solving, which is an integral part

    of handling new or challenging tasks. 44 Particularly dangerous situations at sea arising from sleep debt are brief, uncontrolled and spontaneous sleep episodes while working, termed microsleeps. During a microsleep, the brain disengages from the environment (it stops processing visual information and sounds). Sleep deprivation, which is caused by cumulative sleep debt, can make people more susceptible to microsleeps. The likelihood of microsleeps is even greater if the individual is on duty during a circadian low. 45 The range of effects and signs of fatigue can typically be grouped into three categories: cognitive (e.g. loss of vigilance), physical (e.g. yawning, micro-sleeps) and behavioural (e.g. irritability, mood). The table below outlines some of the major symptoms under each category; however, it is not inclusive. Additionally, many of these symptoms may be subtle.

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    Table 1: Effects of fatigue

    COGNITIVE

    PERFORMANCE IMPAIRMENT SIGNS/SYMPTOMS

    Inability to concentrate Unable to organize a series of activities Preoccupied with a single task Focuses on a trivial problem, neglecting more important

    ones

    Reverts to old but ineffective habits Less vigilant than usual Decline in ability to solve complex problems Lapses of attention Difficulty in multitasking

    Diminished decision-making ability

    Misjudges distance, speed, time, etc. Fails to appreciate the gravity of the situation Overlooks items that should be included Chooses risky options Greater indecisiveness

    Poor memory Fails to remember the sequence of task or task elements Difficulty remembering events or procedures Forgets to complete a task or part of a task Memory lapses

    Slowing of cognitive processes

    Responds slowly (if at all) to normal, abnormal or emergency situations

    PHYSICAL

    PERFORMANCE IMPAIRMENT

    SIGNS/SYMPTOMS

    Involuntary need to sleep Slow eyelid closures

    Droopy eyelids Itchy eye Nodding off Inability to stay awake

    Loss of control of bodily movements

    Affected speech, e.g. it may be slurred, slowed or garbled, or hard to find the right words

    Feeling heaviness in the arms and legs Clumsiness, such as increased frequency of dropping

    objects like tools or parts

    Difficulty with hand-eye coordination skills (such as switch selection)

    Tremors

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    Health Issues Headaches Giddiness Rapid breathing Digestion problems Leg pains or cramps Insomnia Sudden sweating fits Heart palpitations / irregular heart beats Loss of appetite (and sometimes an increase in unhealthy

    eating habits)

    BEHAVIOURAL

    PERFORMANCE IMPAIRMENT

    SIGNS/SYMPTOMS

    Mood change Quieter, less talkative than usual Unusually irritable Decreased tolerance and anti-social behaviour Depression

    Attitude change Fails to anticipate danger Fails to observe and obey warning signs Seems unaware of own poor performance More willing to take risks Ignores normal checks and procedures Displays a "don't care" attitude Less desire to socialize Increasing omissions and carelessness Low motivation

    46 Sleep debt, over long periods of time (more than two weeks), has long-term effects on health and clinical illnesses, increasing the risks of pain, stress, obesity, coronary heart disease, gastrointestinal disorders and diabetes. Long-term effects also point to mental health problems such as negative mood states and depression.

    47 Fatigue is known to affect performance and reduce individual and crew effectiveness and efficiency, decrease productivity, lower standards of work, and may lead to errors. The instances of injuries and incidents reportedly related to fatigue within maritime operations have resulted in great economic, environmental and human cost. Thus, addressing the risks of fatigue and its causes is essential.

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    ILO and IMO instruments related to fatigue

    48 The following IMO instruments contain guidance on fatigue-related aspects: .1 International Convention on Standards of Training Certification and

    Watchkeeping for Seafarers (STCW), 1978, as amended

    .1 Regulation VIII/1 (Fitness for duty) states that "each Administration shall, for the purpose of preventing fatigue:

    .1 establish and enforce rest periods for watchkeeping

    personnel and those whose duties involve designated safety, security and prevention of pollution duties in accordance with the provisions of section A-VIII/1 of the STCW Code; and

    .2 require that watch systems are so arranged that the

    efficiency of all watchkeeping personnel is not impaired by fatigue and that duties are so organized that the first watch at the commencement of a voyage and subsequent relieving watches are sufficiently rested and otherwise fit for duty."

    .2 Regulation VIII/2 (Watchkeeping arrangements and principles to be

    observed) states that "Administrations shall direct the attention of companies, masters, chief engineer officers and all watchkeeping personnel to the requirements, principles and guidance set out in the STCW Code which shall be observed to ensure that a safe continuous watch or watches appropriate to the prevailing circumstances and conditions are maintained on all seagoing ships at all times."

    .3 In addition, part A of the STCW Code sets minimum periods and

    frequencies of rest and requires that watch schedules be posted where they are easily accessible.

    .2 International Safety Management (ISM) Code: This Code introduces

    safety management requirements on ship companies to assess all identified risks (both ashore and afloat) that affect safety (to ship and personnel) and environment and establish appropriate safeguards. The fatigue-related requirements include the requirement for the company to:

    .1 develop, implement and maintain a safety management system

    (section 1.4); .2 ensure that each ship is manned with qualified, certificated and

    medically fit seafarers in accordance with national and international requirements and is appropriately manned in order to encompass all aspects of maintaining safe operations on board (paragraph 6.2);

    .3 ensure necessary shipboard support is provided so that the

    master's duties can be safely performed (paragraph 6.1.3); and .4 provide familiarization and training for shipboard personnel

    (paragraphs 6.3, 6.4 and 6.5).

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    .3 Principles of minimum safe manning (resolution A.1047(27)): This resolution provides guidelines for determining minimum safe manning. In particular in ensuring "fitness for duty", paragraph 1.4.2 of annex 2 states that "in determining the minimum safe manning of a ship, consideration should also be given to the capability of the master and the ship's complement to coordinate the activities necessary for the safe operation and for the security of the ship and for the protection of the marine environment."

    .4 Fatigue factors in manning and safety (resolution A.772(18)): This

    resolution provides a general description of fatigue and identifies the factors of ship operations which may contribute to fatigue.

    49 The following ILO instrument contains guidance on fatigue-related aspects: .1 Maritime Labour Convention (MLC), 2006. Relevant aspects of the MLC

    include, but are not limited to:

    .1 Regulation 2.3: To ensure that seafarers have regulated hours of work or hours of rest.

    .2 Regulation 2.4: To ensure that seafarers have adequate leave. .3 Regulation 2.7: To ensure that seafarers work on board ships with

    sufficient personnel for the safe, efficient and secure operation of the ship.

    .4 Regulation 3.1: To ensure that seafarers have decent

    accommodation and recreational facilities on board. .5 Regulation 3.2: To ensure that seafarers have access to good

    quality food and drinking water provided under regulated hygienic conditions.

    .6 Regulation 4.3: To ensure that seafarers' work environment on

    board ships promotes occupational safety and health. References 1 Allen, P., Wadsworth, E., and Smith, A., (2008). Seafarers' fatigue: a review of the

    recent literature. International Maritime Health, 591(1-4): p. 81-92. 2 Allen, P., Wellens, B. T., McNamara, R., and Smith, A. (2005). It's not all plain sailing.

    Port turn-arounds and seafarers' fatigue: A case study in Contemporary Ergonomics. Hatfield, UK.

    3 American Academy of Sleep Medicine, (2014). International Classification of Sleep

    Disorders. 3rd ed. ICSD-3. Winchester, IL: AASM. 4 Belenky, G., Wesensten, N., Thorne, D. R., Thomas, M. L., Sing, H. C., Redmond, D.

    P., Russo, M. B., and Balkin, T. J., (2003). Patterns of performance degradation and restoration during sleep restriction and subsequent recovery: a sleep dose-response study. Journal of Sleep Research, 12(1-12).

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    5 Carotenuto, A., Molino, I., Fasanaro, A. M., and Amenta, F., (2012). Psychological stress in seafarers: A review. International Maritime Health, 63(4): p. 188-94.

    6 Caruso, C. C., Bushnell, T., Eggerth, D., Heitmann, A., Kojola, B., Newman, K., Rosa,

    R. R., Sauter, S. L., and Vila, B., (2006). Long Working Hours, Safety, and Health: Toward a National Research Agenda. American Journal of Industrial Medicine, 49: p. 930-942.

    7 Costa, G., (1996). The impact of shift and night work on health. Applied Ergonomics,

    27(1): p. 9-16. 8 Dinges, D. F., Pack, F., Williams, K., Gillen, K. A., Powell, J. W., Ott, G. E., Aptowicz,

    C., and Pack, A. I., (1997). Cumulative sleepiness, mood disturbance, and psychomotor vigilance performance decrements during a week of sleep restricted to 4-5 hours per night. Sleep, 20: p. 267.

    9 European Union, (2012). Project Horizon – a wake-up call, European Commission,

    Seventh Framework Programme p. 32. 10 Folkard, S. and Tucker, P., (2003). Shift work, safety and productivity. Occupational

    Medicine, 53: p. 95-101. 11 Folkard, S., (2008). Do permanent night workers show circadian adjustment? A

    review based on the endogenous melatonin rhythm. Chronobiol Int, 25: p. 215-224. 12 Grech, M. R., Horberry, T., and Koester, T., (2008). Human Factors in the Maritime

    Domain. CRC Press. Boca Raton. 13 Härmä, M., (2006). Workhours in relation to work stress, recovery and health. Scand

    J Work. 14 Härmä, M., Partinen, M., Repo, R., Sorsa, M., and Siivonen, P., (2008). Effects of 6/6

    and 4/8 watch systems on sleepiness among bridge officers Chronobiology International, 25(2): p. 413-423.

    15 Houtman, I., Miedema, M., Jettinghoff, K., Starren, A., Heinrich, J., Gort, J., Wulder,

    J., and Wubbolts, S., (2005). Fatigue in the shipping industry, TNO: Hoofddorp. 16 Lützhöft, M., Dahlgren, A., Thorslund, B., Kircher, A., and Gillberg, M., (2010). Fatigue

    at sea: A field study in Swedish shipping. American Journal of Industrial Medicine, 53(7): p. 733-40.

    17 Maritime Accident Investigation Branch, (2004). Bridge Watchkeeping Safety Study,

    MAIB. 18 National Sleep Foundation. (2015.How Much Sleep Do We Really Need? [cited 2015

    20 April]. Available from: http://www.sleepfoundation.org/article/how-sleep-works/how-much-sleep-do-we-really-need

    19 Oldenburg, M., Hogan, B., and Jensen, H. J., (2013). Systematic review of maritime

    field studies about stress and strain in seafaring. International archives of occupational environmental health, 86(1): p. 1-15.

    http://www.sleepfoundation.org/article/how-sleep-works/how-much-sleep-do-we-really-needhttp://www.sleepfoundation.org/article/how-sleep-works/how-much-sleep-do-we-really-need

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    20 Phillips, R. O., (2014). An assessment of studies of human fatigue in land and sea transport., in Fatigue in Transport Report II, Institute of Transport Economics (TØI). Oslo.

    21 Phillips, R. O., Nævestad, T. O., and Bjørnskau, T., (2015). Transport operator fatigue

    in Norway: literature and expert opinion, in Fatigue in Transport Report III, Institute of Transport Economics: Oslo.

    22 Pilcher, J. J. and Huffcutt, A. I., (1996). Effects of sleep deprivation on performance:

    a meta-analysis. Sleep, 19(4): p. 318-26. 23 Rosa, R. R., (2012). Long work hours, fatigue, safety, and health, in The handbook of

    operator fatigue, Matthews, G., Desmond, P. A., Neubauer, C., and Hancock, P. A., Editors. Ashgate Publishing Ltd.: Surrey.

    24 Starren, A., M., van Hooff, M., Houtman, I., Buys, N., Rost-Ernst, A., Groenhuis, S.,

    and Dawson, D., (2008). Preventing and managing fatigue in the Shipping industry, TNO: Hoofddorp.

    25 United States Coast Guard, (2005). Crew Endurance Management Practices:

    A Guide to Maritime Operations, Marine Safety and Environmental Protection: Washington, DC.

    26 van der Hulst, M., (2003). Long workhours and health. Scand J Work Environ Health,

    29(3): p. 171-88. 27 Wadsworth, E. J. K., Allen, P. H., Wellens, B. T., McNamara, R. L., and Smith, A. P.,

    (2008). Patterns of fatigue among seafarers during a tour of duty. American Journal of Industrial Medicine, 49(10): p. 836-844.

    28 Williamson, A., Lombardi, D. A., Folkard, S., Stutts, J., Courtney, T. K., and Connorf,

    J. L., (2009). The link between fatigue and safety. Accident analysis and Prevention, 43(2011): p. 498-515.

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    MODULE 2

    FATIGUE AND THE COMPANY

    1 Module 2 contains guidance for the company in assessing, mitigating and managing the risk of fatigue in operational environments. Is fatigue an important issue in shipboard operations?

    2 Fatigue has been recognized as an important occupational health and safety issue for seafarers. Fatigue has the potential to greatly increase the risk of incidents and injuries in the work place. It disrupts circadian rhythms and results in digestive problems, confusion, lethargy, respiratory problems, depression and irritability. Fatigue adversely affects seafarer performance. It diminishes attentiveness and concentration, slows physical and mental reflexes and impairs rational decision-making capability. 3 Research has established a clear link between fatigue and accidents at sea. Clearly, addressing the issue of fatigue should have a positive effect on personnel safety and has the potential to cut costs for the company by reducing injury and physical damage to high-value assets and the environment. 4 Fatigue poses a risk to any position on board, but especially those that have critical safety and security responsibilities. Should an individual fail to carry out an allotted task due to fatigue, the crew runs the risk of a safety or security incident. Any risk management strategy must focus on mitigating the potential for such hazards to arise by addressing the causes of fatigue. Systems and work procedures should be critically examined to engineer out design deficiencies that could contribute to fatigue. The company should provide an adequate level of support for managing the risks of fatigue at both the organizational and operational levels.

    What elements of fatigue can the company influence? 5 While it is not possible for the company to regulate and oversee the sleeping habits of every seafarer on every ship, it is within its capability to mitigate the risks of fatigue through ship design, operational and manning policies. The Principles of minimum safe manning (resolution A.1047(27)) provides for an assessment of the tasks, duties and responsibilities of the ship's complement to ensure that manning levels are adequate at all times to meet all conditions and requirements including meeting peak workload situations and emergency conditions. Hours of rest are presently controlled by a prescriptive formula set out in chapter VIII of the International Convention on Standards of Training, Certification and Watchkeeping for Seafarers (STCW) 1978, as amended. Managers should be aware (when applying these hours of rest) that considering the effects of circadian rhythm and sleep debt is important for ensuring that rest periods are of high quality. It also cannot be too highly stressed that rest means rest, not substituting a different form of work. This should be supported by appropriate manning, resources, processes and policies, so that fatigue risks can be managed in a way that supports safe, compliant and productive operations. Importantly, fatigue risk control measures forming part of the company support should:

    .1 identify and assess fatigue risks; .2 assess operational workload requirements in accordance with the Principles

    of minimum safe manning (resolution A.1047(27));

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    .3 ensure that manning and resources are adequate and available for assessed workload requirements and to conduct all ship operations safely;

    .4 ensure company-wide awareness of the risk of fatigue; and .5 ensure a healthy shipboard environment. 6 Figure 1 below provides a framework to assess the hazards associated with fatigue and different strategies to mitigate the risk of fatigue.

    Figure 1: Framework to mitigate the risk of fatigue

    7 Companies' records of hours of work and rest are generally assessed against regulatory requirements. Planning tools are available that take into account the circadian rhythm. The use of such planning tools may assist companies in doing the following: .1 Analyse planned work routines to ascertain the risk of fatigue. .2 Monitor work hours on board the ship to determine whether or not the risk of

    fatigue is increasing as a result of the work arrangements or from any variations that may have occurred.

    .3 Analyse and compare information related to hours of work to determine the

    effectiveness of employed routines, compared to other alternatives. 8 It is important that companies adopt a fatigue mitigation and control strategy that is tailored to the individual operational requirements.

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    How can the company ensure that fatigue prevention is practised on board? 9 The company should consider the following: .1 ISM Code requirements for clear, concise guidance on operational

    procedures on board;

    .2 ensure adequate resources, including manning levels;

    .3 promote a safety reporting culture with open communication and no fear of reprisal;

    .4 the need for joining seafarers to be adequately rested before assuming duties;

    .5 schedule time for proper handover on crew change;

    .6 voyage length, time in port, length of service and leave ratios;

    .7 multicultural issues; language barriers, social, cultural and religious isolation;

    .8 interpersonal relationships, stress, loneliness, boredom, social deprivation and increased workload as a result of small crew numbers;

    .9 provision for shore leave and onboard recreation, family communication;

    .10 watchkeeping arrangements;

    .11 job rotation, if practicable;

    .12 adequate sleeping berths and accommodation;

    .13 adequate quality and quantity of food for proper nutrition;

    .14 read other modules of these guidelines for additional potential managerial mitigation tools; and

    .15 modification of present ship design or future designs, if necessary. 10 Fatigue training and awareness are essential components. The company should ensure all personnel have appropriate training. This includes shore-based personnel whose decisions may impact on the management of fatigue (such as those involved in resource planning, including ship manning levels, and duty scheduling decisions) and fatigue-related processes. This is important, as their decisions potentially affect fatigue levels of seafarers and consequently shipboard safety. 11 Initial fatigue-related training should establish a common level of understanding among seafarers and shore-based personnel about the dynamics of sleep loss and recovery, the effects of the body clock on circadian rhythms, the influence of workload, and the ways in which these factors interact with operational demands to produce fatigue (covered in module 1). In addition, it is useful for all seafarers to have information on how to manage their personal fatigue and sleep issues (covered in module 3). 12 This process, as with any other training, should be ongoing in nature. Hence, training should be conducted on an initial and recurrent basis. The interval between training should be determined by the company, given their operational characteristics and training needs analysis.

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    13 Promoting a safety reporting culture is necessary. The company should ensure that processes are in place to provide seafarers with the opportunity to report situations when the seafarer has been unable to obtain adequate sleep or feels at risk of making fatigue-related errors, specifically if conducting safety critical tasks. This process should allow for open communication and reporting between seafarers, their supervisors and the company, and should prohibit any action directed against a seafarer for such communications or reports. Adequate resources (including ship manning levels) 14 Adequate resources, including manning, is one of the primary determinants of seafarers' duty hours, workload, duty scheduling, average time off duty, and other key factors that can have an influence or elevate fatigue. The company should ensure that adequate resources are available with a need to proportionally balance varying work and task demands and deal with unexpected surge to reduce the risk of fatigue across shipboard operations. 15 Manning levels should match the operational workload on board the ships and this workload should be managed efficiently. Operational workload is determined through an assessment by the company. 16 Although the master is responsible for managing the ship and its crew, the company should ensure that the master is adequately supported and resourced to conduct shipboard duties and operations safely and effectively. 17 Effective operational planning is critical to ensuring adequate resources, including manning, are available at all times so that operational and other demands placed on the ship and its crew can be managed safely and effectively. Planning should account for: .1 varying work and task demands within and across days, e.g. amount of time

    the ship is travelling through confined and congested waters and less confined open waters;

    .2 trading patterns, i.e. number of port calls – the more port calls the higher the

    workload; .3 planning for disturbances, such as weather, ship movement in port, port entry

    and exit delays and port surveys and inspections; .4 ensuring adequate manning is available to cover planned and unplanned

    aspects such as training, illnesses, injuries and sickness; and .5 ensuring company commercial obligations or interests do not impinge on or

    affect safety in any way.

    18 The company should consider strategies to deal with periods of high workload and to manage this accordingly. Appropriate strategies may include the following: .1 The allocation of crew numbers to peak times and demands is a fundamental

    factor in minimizing the exposure to risks associated with extended duty hours. Numbers and types of seafarers should be scheduled based on predictable operational demands to account for daily, weekly and monthly operational trends.

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    .2 Ensure the master is well resourced and supported to carry out all shipboard tasks safely and to allow for unexpected surge and overriding operational conditions.

    .3 Ensure there are adequate resources, including manning, available to

    complete shipboard tasks safely without placing excessive demands on seafarers.

    .4 Augment with shore-based support or additional rest when the ship is in port,

    such as during loading and unloading and port inspections, to ensure shipboard crew obtain adequate time off for rest and sleep and are fit for duty when the ship leaves port.

    .5 Provide shipboard administrative support or a means for relieving the burden

    associated with paperwork and related administrative tasks. .6 Where practicable, provide remote support to shipboard crew in areas such

    as paperwork, loading/unloading calculations.

    .7 Utilize other crewing concepts, such as the use of port captains and/or shore-based crew.

    .8 Plan arrival and departures (tides in ports, delays due to weather, pilotage

    boarding, etc.) to take into account adequate sleep and rest. 19 An important aspect that needs to be mentioned is that of "overriding operational conditions". In accordance with section B-VIII/1 of the STCW Code "overriding operational conditions" should be construed to mean only essential shipboard work which cannot be delayed for safety, security or environmental reasons or which could not reasonably have been anticipated at the commencement of the voyage. This means that they should not be occurring on a regular basis. Planning, using risk assessment tools and operational experience, can foresee these potential disruptions or delays, e.g. weather, port inspections, traffic congestion during departure/arrivals and illness of seafarers. Healthy shipboard environment 20 Seafarers are required not only to work but also to live on board a ship. Hence, ensuring a healthy shipboard environment is crucial to minimizing the risks of fatigue. The most important aspects should include: .1 Healthy eating: healthy nutritious food is available and served on board and

    crew afforded unlimited access to drinking water. .2 Healthy sleep: the shipboard sleeping environment should provide for

    comfortable and good quality sleep (bedding, pillows, mattresses, adequate light management, etc.).

    .3 Exercise: adequate exercise facilities are provided (such as well-designed

    and equipped training facilities and outside spaces), to ensure seafarers can maintain a healthy lifestyle on board.

    .4 Stress: adequate shipboard measures are in place to recognize and ensure

    adequate support to seafarers suffering from stress.

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    21 Furthermore, initial ship design plays a part in ensuring a healthy operational environment (see module 5). Adequate sleep opportunity 22 Effective fatigue management is predominantly about ensuring that seafarers are provided with adequate sleep opportunity. 23 It is not correct to assume that a given rest period from duty will provide a given level of sleep and hence recovery. The length of the rest period is only one key factor. The relationship between the recovery value of off-duty periods and the actual amount of sleep obtained in a shipboard environment is increasingly complex. As highlighted in module 1, sleep quantity and quality (and its restorative value) depends on going through uninterrupted sleep. The more sleep is fragmented by waking up, the less restorative value sleep has in terms of how seafarers feel and function when they are on duty. 24 Shipboard-related factors that affect sleep include the design of duty schedules, i.e. length and timing of duty periods, length and timing of breaks within and between a duty period, and the environment, e.g. heat, humidity, noise, vibration, lighting levels, ship routines, diet. These can all have negative effects on the amount of time seafarers are allocated for sleep in a 24-hour period. Duty scheduling and planning 25 Duty scheduling and planning is a key factor in managing fatigue. Hence, the company should be responsible for ensuring duty schedules provide adequate opportunity for sleep. 26 Companies must, at the very least, be in compliance with STCW regulation VIII/1. 27 From a practical perspective, it is important to determine whether a given duty schedule, on average, enables adequate sleep opportunity. There are seven primary duty schedule considerations that should be taken into account when scheduling. They are: .1 Work hours (work periods): as indicated in module 1, as the length of a

    given period of work increases, the subsequent sleep opportunity decreases. Research has demonstrated that, apart from a reduction in performance, extended hours of work are also associated with reduced individual well-being, reduced organizational commitment and poor health outcomes. Administrative work, shipboard drills, training, ship loading and unloading tasks are all tasks that may affect seafarers' opportunities to gain adequate sleep. These factors in turn have been linked to declining levels of productivity and safety.

    .2 Rest hours (rest periods) between work periods: this is the length of time

    off between work periods and should reflect the fact that seafarers do not simply fall asleep as soon as they are off duty and wake just before they go back on duty. Seafarers, like shore-based workers, have many activities and responsibilities to manage between work periods such as eating, showering, socializing with other crew, relaxing, studying and writing to and communicating with family members and friends back home. Fatigue increases as the number of rest hours decrease; therefore rest hours should provide for adequate sleep opportunity, time to complete those other tasks noted above, be adaptable to the individual circadian rhythm and account for

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    the effects of sleep inertia after waking. Hence, the interval between two successive work periods should allow sufficient time to obtain adequate sleep before the start of the next work period.

    .3 Night watches or work: as indicated in module 1, seafarers working during

    night-time, specifically during the circadian low, can experience severe performance degradation initially. If the seafarer maintains a regular schedule they may adapt over time. However, it is important to provide those seafarers working during night-time with a good sleeping opportunity and environment during the day.

    .4 Short rest breaks within work periods: short rest breaks benefit

    performance and help maintain alertness. As indicated in module 1, one of the most important determinants of fatigue is "time on task". Frequent short breaks are associated with performance benefits and result in better fatigue management when the timing of rest is at the discretion of the individual. While it is recognized that this may not always be feasible in a shipboard environment, it should be noted that the "time on task" effect can also be reduced during the work period by task rotations/substitutions.

    .5 Naps: naps are an effective countermeasure to fatigue, exhaustion from long

    work hours and restricted sleep. Whether before an anticipated short night's sleep or after, brief naps improve performance and alertness, and delay fatigue-induced performance degradation. Overall, research has shown that the benefits of controlled napping outweigh the potential risks associated with sleep inertia.

    .6 Recovery sleep: the provision for sufficient recovery time following periods

    of sleep debt is important. It should be noted that provision of minimum rest periods may not sufficiently acknowledge the critical role that the circadian rhythm plays in the rate at which fatigue accumulates and the rate at which people recover. To work safely across a given duty and to then return to the next work period sufficiently recovered requires that the seafarer obtains sufficient quantity and quality of sleep between work periods. Sleep opportunities during the circadian low are preferable because sleep that occurs during the circadian low provides the most recuperative value.

    .7 Reset breaks: as the risk of fatigue increases over successive work days of

    sleep debt, it seems logical that some "recovery" must take place over spans of rest days. This is typically an issue at sea as seafarers are exposed to potentially arduous duty schedules over a long period of time (in excess of seven days, sometimes months on end) without the possibility of a reset break. It is recognized that in a shipboard environment this is likely not practical; however, this may be a factor to consider when determining crew rotation.

    28 Companies should consider napping and short break policies to manage fatigue if practicable. 29 Companies should also acknowledge impairment through sleep inertia when planning tasks and activities, giving adequate time for seafarers to be alert before performing critical tasks, when possible.

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    Tools to assess fatigue in scheduling 30 The planning of duty schedules based on fatigue science as well as operational requirements permits predictive identification of fatigue hazards. This assists in allocating adequate rest periods that provide sufficient sleep opportunity. 31 There are useful additional tools for the mitigation and control of fatigue such as: .1 fatigue risk assessment tools: the risk level of a specific duty schedule may

    be assessed via a fatigue risk score; and .2 fatigue predictive software tools: models and related software to predict

    fatigue levels for specific operations can be useful additional tools for the management of fatigue risks, as mentioned in paragraph 7.

    32 Such tools should not be used in isolation nor be the main driver for duty scheduling decisions, as they are not sufficient to determine the full extent of fatigue-related risk. They should always be supported by other operational data. Their main purpose should be limited to identifying potentially fatigue-inducing duty schedules or scheduling hot spots and allow for better decisions in the selection of duty schedules. This is because numerous unforeseen circumstances can cause changes to planned schedules, e.g. weather conditions, unexpected technical problems or seafarers' illnesses. Seafarer fatigue is the result of what is actually worked, not what is planned. Thus another proactive approach for identifying fatigue hazards is to analyse actual duty schedules in operation. Workload management 33 As discussed in module 1, mental and physical demands of work can contribute to a seafarer becoming impaired by fatigue in a number of ways. Concentrating for extended periods of time, performing repetitious or monotonous work, and performing work that requires continued physical effort can increase the risk of fatigue. Mental fatigue and physical fatigue are different and a seafarer can experience them at the same time. It is important to be aware of a seafarer's optimal level of workload and stress, and to have realistic attitudes towards these. Understanding that different people react differently to stressful situations (such as emergencies, family problems at home, job-related) is critical for effective interventions. Hence, the use of effective communication with seafarers and monitoring and observing any behaviours that may indicate a change to a seafarer's fatigue as a result of workload is important (see fatigue signs and symptoms in module 1) . 34 Typical techniques for managing workload while on duty include prioritization of tasks, task delegation, task rotation, crew rotation and task shedding. A list of risk mitigation strategies that should be used in managing workload may include: .1 Carefully considering task design according to the workload and the

    available resources, including manning. .2 Reducing the amount of time seafarers need to spend performing sustained

    physically and mentally demanding work (e.g. tank cleaning, navigation through congested waters).

    .3 Managing workload and work-pace change caused by machinery

    breakdowns and planned and unplanned sicknesses and illnesses.

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    .4 Where practicable, minimizing routine and administrative tasks or redesigning them to ensure seafarers can focus on core duties in their working time.

    .5 Minimize repetitive or monotonous tasks by using task rotation, where

    practicable. .6 Where practicable, defer non-urgent work to allow appropriate rest and

    recovery if necessary. Work and living environment 35 The work and living environment is important for ensuring adequate opportunity for sleep and should be considered. Because good quality sleep is critical, companies should develop procedures to minimize interruptions to seafarers' sleep. Opportunities for implementing countermeasures in this area vary from shipboard environmental, procedural to operational changes. For example, most environmental aspects such as noise can be better addressed during ship design (see module 5). However, there are control measures that the company can implement to assist in reducing noise levels in the sleeping environment. 36 Environmental, procedural and operational measures may also range from low-cost solutions, such as porthole blinds and door baffles, to high-cost solutions, such as refitting the ship exhaust or air conditioning systems. 37 Operational and procedural changes may include developing napping policies or defining blocks of time (sleep opportunities) during which seafarers are not contacted except in emergencies. These protected sleep opportunities need to be known to all relevant personnel. Depending on the situation, changes should be made to those areas that will have the most impact, and following evaluation, consideration to other changes can then be made. 38 Environmental control measures may include, but are not limited to: .1 adequate facilities for rest, sleep and meal breaks and other essential

    requirements, such as bathroom facilities and personal storage; .2 making sleeping areas darker, quieter and more comfortable and increasing

    lighting in certain areas of the ship, such as: .1 providing a dark sleeping atmosphere using blackout blinds for

    portholes or berths in sleeping spaces; .2 installing insulation baffles over cabin door louvres; .3 improving air conditioning (ambient temperature) and air flow; and .4 supplying good quality and comfortable bedding such as mattresses

    and pillows; .3 making sleeping spaces, including their location, a priority in retrofitting and

    new ship construction; and .4 ensuring adequate personal storage space is available for seafarers'

    personal effects.

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    39 Procedural and operational control measures may include, but are not limited to: .1 increasing access to healthier food choices by ensuring nutritious food is

    served on board; .2 providing information and advice on healthy eating and physical well-being;

    .3 making exercise equipment and facilities available to seafarers;

    .4 providing and maintaining a quiet atmosphere for sleep; develop a "do not disturb" policy for sleeping seafarers;

    .5 where practicable, calls for drills should be conducted in a manner that minimizes the disturbance of rest periods as they can be extremely disruptive;

    .6 putting in place short breaks within duty periods, including napping policies;

    .7 ensuring ship routines such as meal times are commensurate with seafarer working schedules; this includes providing personnel working at night with appropriate meal choices;

    .8 providing access to counselling services to assist in any issues arising from the disruption to individual, family or social patterns and shipboard-related aspects; implement a consistent stress management programme;

    .9 have a policy in place to support seafarers experiencing elevated levels of workload;

    .10 if possible, avoid assigning seasick and ill seafarers shipboard work;

    .11 if possible, provide all seafarers with shipboard phone, internet and email access; and

    .12 if possible, ensure that maintenance work does not disrupt personnel

    sleeping. Adequate sleep obtained 40 Given that sleep loss is a primary contributor to fatigue, the company should determine whether adequate sleep is obtained. 41 Situations may arise where a seafarer is provided with an adequate sleep opportunity, but they may not get adequate sleep. Hence, while an adequate sleep opportunity provides an indication of the quantity of sleep likely to be obtained, it is important to know whether adequate sleep has actually been obtained. Seafarers should be provided with the opportunity to report situations when they have been unable to obtain adequate sleep or feel at risk of making fatigue-related errors without repercussions. 42 In general, seafarers are responsible for using adequate sleep opportunity appropriately, so they are alert and capable of performing assigned shipboard work safely. However, there are a number of reasons why seafarers may not obtain adequate sleep. The aspects mentioned below can all affect the amount and quality of sleep obtained: .1 a seafarer working during the night may have difficulty getting quality sleep;

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    .2 a seafarer upon joining the ship may experience difficulty adjusting to the sleep schedule;

    .3 a seafarer travelling for an extended time to the ship should not be required

    to report to work until adequate rest is obtained; .4 undiagnosed and untreated sleep disorders as highlighted in module 1; .5 emotional stress; .6 the sleeping environment (comfort, noise, darkness, ship motion, privacy,

    room location) may not allow for adequate sleep; .7 the type of food consumed; .8 medication or use of prescribed/over-the-counter/natural remedies; .9 consumption of stimulants such as caffeine and amphetamines; and .10 use of personal electronic devices before sleep, which may delay the onset

    of sleep and not allow adequate sleep to be obtained. 43 Regardless of the circumstances causing insufficient or poor quality sleep, these should preferably be identified through proactive measures and treated as a potential shipboard hazard. What rules and regulations are in place to prevent and deal with fatigue (international, national and company)? 44 Reference is made to the instruments mentioned in module 1. References 1 Akerstedt, T., Anund, A., Axelsson, J., and Kecklund, G., (2014). Subjective

    sleepiness is a sensitive indicator of insufficient sleep and impaired waking function. Journal of Sleep Research, 2014(23): p. 242-254.

    2 Dawson, D., Noy, Y. I., Härmä, M., Åkerstedt, T. and Belenky, G., Modelling fatigue

    and the use of fatigue models in work settings, Accident Analysis & Prevention, Vol. 43, Issue 2 (March 2011), pp. 549–564.

    3 Dawson, D. and McCulloch, K., (2005). Managing fatigue: It's about sleep. Sleep Med

    Rev, 9(5): p. 365-380. 4 Gander, P., Hartley, L., Powell, D., Cabon, P., Hitchcock, E., Mills, A., and Popkin, S.

    (2011). Fatigue risk management: Organizational factors at the regulatory and industry/company level. Accident analysis and Prevention, 43(2): p. 573-590.

    5 Grech, M. R. (2016) Fatigue Risk Management: A Maritime Framework, International

    Journal of Environmental Research and Public Health, Vol. 13, No. 2 (2016), pp. 175-184. 6 Johnson, J. V. and Lipscomb, J., (2006). Long Working Hours, Occupational Health

    and the Changing Nature of Work Organization. American Journal of Industrial Medicine, 49: p. 921-929.

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    7 Philips, R. (1998). Fatigue Among Ship's Watchkeepers: A Qualitative Study of Incident at Sea Reports in Managing Fatigue in Transportation: 3rd Fatigue in Transportation Conferences, Fremantle, Western Australia: Elsevier.

    8 Rosa, R. R., (2012). Long work hours, fatigue, safety, and health, in The handbook of

    operator fatigue, Matthews, G., Desmond, P. A., Neubauer, C., and Hancock, P. A., Editors. Ashgate Publishing Ltd: Surrey.

    9 Tucker, P., (2003). The impact of rest breaks upon accident risk, fatigue and

    performance: a review. Work and Stress, 17(2): p. 123-137. 10 Tucker, P. and Folkard, S., (2012). Work Scheduling, in The handbook of operator

    fatigue, Matthews, G., Desmond, P. A., Neubauer, C., and Hancock, P. A., Editors. Ashgate Publishing Ltd: Surrey.

    11 Williamson, A. and Friswell, R., (2011). Investigating the relative effects of sleep

    deprivation and time of day on fatigue and performance. Accident analysis and Prevention, 43(3): p. 690-697.

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    MODULE 3

    FATIGUE AND THE SEAFARER 1 Module 3 contains practical information intended for the seafarer (master, officers, ratings and all other shipboard personnel) working on ships. Prior to reviewing this module, it is strongly recommended that all seafarers become familiar with module 1 (Fatigue) first. Management-level seafarers (master and officers) should also become familiar with module 2 (Fatigue and the company). 2 Although the company is primarily responsible for creating a work and living environment that minimizes fatigue-related risks, seafarers are responsible for ensuring that time available for rest and sleep is used appropriately and that their behaviour does not create or increase risk. 3 The maritime industry operates a variety of work schedules in a wide range of operational environments, which means that at some point seafarers are likely to experience fatigue. Fatigue affects all individuals, regardless of skill, rank, knowledge or training. How to recognize fatigue (signs/symptoms)? 4 Fatigued individuals are poor judges of their own level of fatigue and performance because fatigue affects their ability to make judgements or solve complex problems. 5 Fatigue-related signs and symptoms are often divided into three categories: cognitive, physical and behavioural (see table 1 in module 1). Seafarers may recognize some of these in others and, with time, lessons can be learnt to identify some within themselves. These signs and symptoms of fatigue may be used to identify an individual's level of alertness. 6 Some of the more apparent signs and symptoms include: .1 cognitive:

    .1 focuses on a trivial problem, neglecting more important ones; .2 slow or no response to normal, abnormal or emergency situations; .3 lapses of attention; .4 poor judgement of distance, speed, time, etc.; .5 forgets to complete a task or part of a task; and .6 difficulty in concentrating and thinking clearly.

    .2 physical:

    .1 inability to stay awake (an example is head nodding or falling asleep involuntarily);

    .2 difficulty with hand-eye coordination skills (such as switch

    selection);

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    .3 speech difficulties (it may be slurred, slowed or garbled); .4 increased frequency of dropping objects like tools or parts; and .5 digestion problems;

    .3 behavioural:

    .1 decreased tolerance and/or anti-social behaviour; .2 irregular/atypical mood changes (examples are irritability, tiredness

    and/or depression) .3 ignores normal checks and/or procedures; and .4 increasing omissions, mistakes, and/or carelessness.

    7 Long-term effects of sleep loss may lead to cardiovascular diseases, gastrointestinal diseases, mental health problems and stress. 8 The more signs and symptoms seafarers observe in others and/or experience themselves, the more likely it is that alertness is significantly reduced. Fatigue is not the only cause of such symptoms, but when several occur together, it is likely to indicate fatigue-related impairment. It is important that seafarers notify crewmates and supervisors when they recognize that they or other crew members are fatigued. It is important to have open communication between seafarers, their crewmates and their supervisors regarding fatigue prevention and detection. The company's fatigue risk mitigation strategy should allow for open communication and reporting between seafarers, their supervisors and management levels regarding fatigue prevention and detection, and should prohibit any action directed against a seafarer for such communications or reports. What can seafarers do to help reduce and manage the risk of fatigue on ships? 9 Obtain adequate sleep: The most effective strategy to fight fatigue is to obtain adequate quality, quantity and continuity of sleep. As indicated in module 2, the company should provide seafarers with an adequate sleep opportunity for recovery. Insufficient sleep over several consecutive days will impair alertness; only sleep can maintain or restore performance levels. 10 Sleep is most valuable if obtained in a single block. While a short sleep or nap can provide a powerful boost in alertness, it does not eliminate the need for longer periods of sleep. 11 There may be instances when seafarers may not obtain adequate sleep, even though they are provided with adequate sleep opportunity. The items mentioned below can all affect the quantity and quality of sleep obtained:

    .1 seafarers are working during the night and may simply be unable to sleep during the day;

    .2 seafarers' sleep may have been interrupted by colleagues, unexpected

    events or operational demands; .3 seafarers may suffer from a sleep disorder, or other medical or physical

    problem that keeps them awake;